PROJECT SUMMARY The Center for Pediatric Research aims to understand regulators of cellular pliancy in the developmental origin of health and disease (DOHaD). Project 3 will determine the role of mitochondria and cellular metabolism in cardiomyocyte fate as a key mediator of heart disease in offspring born following a diabetic pregnancy. Infants who are born to mothers with diabetes or obesity are at higher risk of heart disease at birth and in adulthood, purportedly through fuel-mediated influences on the developing heart. However, preventative and therapeutic interventions are lacking because the underlying mechanism remains unknown. The Baack Lab is well poised to solve this problem as it builds upon their recent discovery that maternal diabetes, especially with a high-fat diet, incites mitochondrial dysfunction, altered cellular bioenergetics and cardiomyopathy in the developing offspring's heart. Moreover, exposure to diabetic pregnancy was sufficient to extend these cardiometabolic consequences into adulthood. The proposed project builds upon this discovery using The Baack Lab's well-characterized and physiologically relevant rat model, advanced systems biology tools, state-of-the-art live-cell metabolic assays, and mesenchymal stem cell derived cardiac progenitors from human umbilical cords exposed to normal or diabetic pregnancy. The proposed methods will uncover mechanisms of pathogenesis and translate findings to humans while answering two unresolved questions: 1) How does diabetic pregnancy cause mitochondrial dysfunction and altered cellular bioenergetics in the developing offspring's heart? 2) What are the downstream effects on cell pliancy, specifically cardiomyocyte proliferation, differentiation and senescence as it relates to developmentally programmed heart disease? Together with the Center for Pediatric Research, Project 3 will demonstrate the role of mitochondria and metabolic plasticity in stem cell regulation and set a firm foundation needed to develop pre- and post-natal interventions to prevent heart disease in this growing at-risk population.